Sterilization Chapter 10

Chemical Monitoring : Process indicators Type 1

-These are external CIs, used to differentiate packages that have NOT been processed in a sterilizer from those that have. (e.g autoclave tape/sterilizer tape)

how to unload the sterilizer:

-leave items on the cart untouched in a low traffic area, away from air vents until they are completely cool. (30 min-2 hours) -unload with clean hands -handling warm packs can cause wicking that contaminates the pack.

loading the sterilizer :

-place mesh bottom pans flat on the sterilizer rack--maintains distribution of metal mass, keeps instruments in an orderly way and prevents instruments damage -solid bottom trays or those with small holes-tilted on their edge--permits condensate to run off esp. Mayo trays (has small holes) the small holes in the Mayo tray do not permit adequate drainage of condensate when placed flat; -heavier sets- should be placed on the bottom of the racks because they tend to produce more condensate do not stacked wrapped items

Drying :

is critical to sterility maintenance if packages are still moist when the sterilizer door is opened, bacteria can land on the packages and "wick" or travel inside the package. the total metal mass weight of the load affects drying the steam quality the loading configuration of the sterilizer In a pre-vacuum sterilizer, the drying takes place in HEPA-filtered air in a gravity displacement sterilizer, drying takes place by evaporation (less efficient )

paper plastic pouches should be placed:

on their edge (side) with the clear side of one pouch facing the paper side of the next pouch

What is wicking?

organisms enter through packages when it is still warm or moist.

sterilitiy

the absence of ALL microbial life Microorganisms are inactivated by the sterilization process described in terms of probability less than one in a mil chance that a viable microorganism survives a sterilization process that is designed to kill one million bacterial spores.

Stacking of rigid containers on the autoclave rack is permitted when?

the manufacturer provides technical data showing that it is acceptable

what happens if a package has moisture on the outside of the pack at the end of the sterilization cycle?

the package should be completely reprocessed

Chemical Monitoring : Type 5 integrating indicators

their response depends on the achievement of ALL of the critical parameters they were designed to monitor. provides immediate information regarding the sterilizers ability to achieve all necessary sterilization parameters parallels the performance of BIs -not to be used as a substitute for a BI -may be used as an internal CIs and in a PCD to monitor non-implant loads can be used to release an implant before the BI result is available, in defined emergency situations

Basin sets or other devices that can collect and retain water should be :

tilted forward on their side in the same direction to drain condensate

For sterilization, basin sets should be positioned:

tilted on their side

Place textile packs on their side.. why?

to facilitate air removal (through the folds) and steam penetration. Do not place flat. In the proper position the folds of the textile pack should be vertical in relation to the cart.

Steam sterilization phases of cycle : PHASE ONE

1. conditioning phase- air is removed from the sterilizer chamber and steam is injected. gravity-displacement cycles- the steam passively displaces the air through a port or drain in the bottom of the sterilizer dynamic air removal cycles- air is actively removed by one or more vacuum excursions the packs within the sterilizer are gradually heated by steam length of the conditioning phase varies with the materials in the load and is controlled by the sterilizer

when is QT testing used

1. when a new sterilizer is installed 2. when a sterilizer is relocated 3. when a sterilizer malfunctions 4. when a sterilizer or its utilities has had a major repair 5. after a sterilization process failure that requires a major repair

sterility assurance level (SAL)

10 to the -6th

99.9999

10(-6)

Steam sterilization phases of cycle PHASE 2

2. sterilization/ exposure/ holding phase: the exposure temp is maintained for the prescribed amount of time example: if the sterilizer is set for 4 minutes at the set temp.

Excessive heavy sets of ______ lbs contribute to most of the damage

25lbs

Dynamic air -removal steam 4 minutes at ______

270 degrees and 28-30 psi steam pressure

Run the cycle specified for a bowie-dick test or run at :

3 3/2 minutes at 270 degrees f with no drying if the cycle could not be set for 3 1/2 minutes the cycle should be run for 4 min

List the characteristics of medical devices for which each sterilization method is suitable :

A) High temperature sterilizer -heat resistant, moisture resistant (surgical instruments-stainless steel) 1.Steam 2. Dry Heat B) Low temperature sterilizer -Heat sensitive , pressure sensitive , moisture sensitive (fiberoptic light cables, cameras, rigid endoscopes 1.E/O 2.LTGP 3.LTHP 4.HP-Ozone

Sterilizer Qualification Testing

BI testing should also be performed when: -a sterilizer is installed or relocated -after a malfunction requiring a major repair of the sterilizer or its utilities and after a sterilization process failure that requires major repair. -BI PCD tests should be performed before the Bowie Dick Test

why is complete air removal important ?

Because air will interfere with steam contact of the device

Among the 4 monitoring systems, which is the one that proves the lethality of the sterilization process?

Biological monitoring system (BI)

Steam sterilization phases of cycle PHASE 3

Exhaust phase: after the exposure phase, steam is exhausted from the sterilizer through the chamber drain line

When is the Bowie-Dick Test performed?

First cycle of the day same time each day

How do steam sterilizers work?

First, the sterilizer needs a dedicated supply of STEAM, which is generated in boiler. Feed water to boiler is treated with chemicals

Spores used for steam is ___________ _____________

Geobacillus stearothermophilus this spore is most resistant to steam test pack is called a process challenge device (PCD) identify sterilizer and the load or cycle with a lot control label affixed outside the BI PCD

where is the thermometer located?

In drain line

Where are sterilizers area located?

In the prep and pack area, adjacent to the sterile storage area.

a gravity displacement liquid cycle - slow exhaust to prevent rupture of the liquid container at the end of the cycle

Liquids

Prevacuum or SFPP : what type of test, number of tests needed, how to run?

PCD (BI test pack) Bowie Dick test for prevacuum sterilizers number of tests needed 3 how to run: back to back in empty chamber

Extended sterilization is required to destroy :

PRIONS

Which of the 2 BIs is positive? which is negative? which BI indicates an ineffective sterilization

YELLOW IS POSITIVE PURPLE IS NEGATIVE yellow is ineffective

if a wet pack is noted to be wet, should you open up the other sets to observe for moisture ?

YES

immediate use steam sterilization may by indicated when

a one of a kind instrument is contaminated

What is the difference between a wet pack and a wet load?

a wet pack is a package that has visible moisture , such as droplets on the outside or inside such as a wet towel or tray liner, moisture on the instruments, or visible water inside the set a wet load consists of multiple wet packs found in the same load.

Sterile penetration can be invited by using :

a wrapper that is too large

Sterilization print outs must be signed: a. at the end of each cycle b. at the end of each shift c. at the end of the day d. at the end of the week

a. at the end of each cycle

A class 2 chemical indicator resulted in an incomplete color change, what must immediately be done? a. document and repeat the test b. clear the sterilizer for use c. call the manufacturer d. stop the the sterilizer from further use

a. document and repeat the test

the bowie dick test is used to monitor ? a. dynamic -air removal cycles b. internal chamber temp c. gravity steam cycles d. diagnostic performance

a. dynamic air removal cycles

Presecens of cause stains on instruments and packaged items

amines

Chemical Monitoring : Type 4 Multi-variable indicator

are multi parameter indicators. Their response depends on the achievement of two or more of the critical parameters of the specific sterilization process that they were designed to monitor. e.g acceptable end point via color change, the proper storage conditions, the expiration date -need to follow MI

Chemical Monitoring : type 3 single variable indicators

are single parameter indicators. they respond to only one parameter of a sterilization process e.g glass ampule containing a chemical that melts when the sterilization temp is achieved

for testing of rigid sterilization containers, biological indicators should be placed: a. in the two opposite corners of the inner basket and the lid b. as recommended by the manufacturer of the container c. in the center of the inner basket and the center of the lid d. in each corner of the basket and under the center of the lid

b. as recommended by the manufacturer of the container

A Class 5 indicator is called a(n)? a. process indicator b. integrating indicator c. multi-parameter indicator d. single -parameter indicator

b. integrating indicator

Sterilizer Access area is located where ?

behind the sterilizers to allow service access

All loads containing implantable devices should be: a. monitored with the patients name b. recorded with the surgeons name c. monitored with a biological indicator

c

how many spores does a vial biological indicator have? a. 1000 b.10000 c.1000000

c. 1000000

The most unique feature of a type 5 chemical integrator is its ability to: a. be incubated and read within 3 hours b. be suitable for all types of sterilization c. perform in parallel to a BI

c. perform in parallel to a BI

Regardless of the method of air removal, air and steam both exit through the _______ ________

chamber drain

the bowie dick test is considered which type of monitoring process

chemical type 2

Biological indicators BI contain ?

contains 1 million spores (1,000,00 ---- 10(6)

when should you clean the drain line?

daily

Documentation questions:

document all cycles run, daily bowie dick air removal tests, routine sterilization cycles, qualification test cycles and aborted cycles. -surgical instruments tracking system allows all sterilization and BI information to be scanned in. -description of the items-specific not generic in the using dept.

when performing routine maintenance cleaning of the steam sterilizer, what are the two most important parts to check

drain line basket and the door gasket.

Special cycles for processing instruments exposed to PRIONS

equipment with known or suspected prion (CJD) exposure require proper cleaning and special sterilization cycles must be processed unwrapped pre-vacuum 273 degrees for 18 min Gravity displacement 250 degrees for 60 minutes

Most contamination occurs with the ________ hour of sterilization

first

The Recall should include documentation of all of the following:

how many items recalled were actually retrieved which items could not be retrieved verification that the recalled items were reprocesses or destroyed. the reason for the recall the outcome of the investigation of the sterilization process failure any corrective actions information regarding any items used before they could be retrieved should also be included.

What does IUSS stand for?

immediate use steam sterilization most often located in operation rooms and ambulatory surgery centers, some in labor and delivery dept appropriate in "emergency" situations as when a one of a kind item is dropped on the floor during surgery or in contaminated and is needed urgently.

steam quality

important to successful sterilization and effective drying incoming steam should be 97%-100% dry saturated steam 3% entrained water steam sterilization occurs by condensation

Temp and pressure

in a sterilization cycle temp and pressure are interrelated For each temp there is necessary PRESSURE to reach that temp Chamber pressure is affected by by atmosheric pressure -above sea level-low pressure -below sea level -higher pressure

Types of PCDs

two types available for sterilizers larger than 2 cubic feet. PCD with conventional BI vial-incubated 48 hours after sterilization can be used to monitor 270 to 275 dynamic air removal and 250 gravity displacement cycle includes type 5 integrating indicator for implants PCD with an enzyme-based early readout BI- provides a final reading in 3 hours detects flourencense: positive= ineffective sterilization no fluorescece : BI is inactive = effective sterilization

Gravity displacement sterilizer: what type of test, numbers of tests needed, how to run?

type of test: PCD (BI test pack) number of tests needed: 3 how to run: back to back in an empty chamber

IUSS is wrapped or unwrapped in mesh bottom, perforated open tray

unwrapped

Gravity-displacement Cycle

used for medical devices that CANNOT withstand the temp or vacuum of a dynamic air removal sterilization packs are more difficult to dry- drying takes place by evaporation through chamber walls

What is ethylene oxide?

used for the sterilization of heat, pressure or moisture sensitive items, most stable low temperature sterilant

what is an infrared thermometer used for?

used to determine the temp of packs. if such a device is used, it is NOT necessary to touch packs to determine whether they are cool. The suggested release temp is 75F

Chemical monitoring: Type 2 indicators for specific tests

used to test certain procedures e.g Bowie Dick Tests are used to test the air evacuation system on pre-vacuum sterilizers

Wet Steam can cause?

wet packs

a clogged drain line can contribute to:

wet packs and inadequate air removal and sterilization failure

Reprocess load:

when a positive BI indicates a sterilization failure due to operator error. e.g not selecting the correct cycle

Retrieve all items since the last negative BI and reprocess when

when a positive BI indicating sterilization failure is NOT due to operator error.

Most important log info about why IUSS was used

write the reason why it was used

______ sterilization is a product of heat plus moisture

Steam

What is SUPERHEATING?

Steam pressure is too low for the set temp

Monitoring systems:

-Administrative monitoring --policies and procedures -physical monitoring-observation and documentation of charts, graphs and printouts (sterilizer operator should verify all parameters met) -Chemical monitoring--involves the use of internal and external indicators/integrators to verify that the items have been exposed to one or more conditions necessary for sterilization and e.g bowie dick test to verify that their air removal mechanism is functioning properly. -Biological monitoring --Using a biological component to prove lethality -Biological monitoring (BI) - is intended to verify that the sterilization conditions within the load was adequate to kill a known number of bacterial spores. The only way to measure the lethality of the sterilization process.

Adjustments to avoid wet packs:

-Assembly of instruments in set -size of peel pouches used to package the load contents -basin packaging and loading -loading techniques --is there too much metal mass in the load, are textile items on the top of the rack and metal items in the bottom -selection of cycle parameters -- was the sterilization cycle correct for the load contents? Check the IFUs -drying time -unloading and cooling--is the room temp appropriate

Causes of Wet Packs

-Packs were improperly prepared or loaded. -heavy or dense instrument sets. exceeding 25lbs -Not using absorbent material to wick moisture between heavy metal (basins). -Textiles wrapped too tight. -Items wrapped while still damp or moist. -Gasket not intact. -Clogged chamber drain screen.

high temperature sterilization: (1)

DRY HEAT STERILIZATION (WITHOUT STEAM)

Chemical Monitoring: Type 6 Emulating indicators :

Designed to react to all critical variables of the specific sterilization process that they are designed to monitor. -They are cycle verification indicators and are labeled for the specific sterilization cycle that they re intended to monitor. -must be used for the cycle type and specific temp indicated. -they do not contain spores and should not be used as a substitute for a BI -may be used as an internal CI and inside a PCD to release non-implant loads.

without moisture the effect is that of ?

Dry heat sterilization

Steam sterilization phases of cycle: Phase 4

Drying phase: After steam has been exhausted, the sterilizer goes into the drying phase of the cycle, which typically lasts about 30 min dynamic Air removal -filtered air is drawn into the chamber Gravity-displacement - the heat in the chamber walls causes moisture to evaporate.

The DART test is ? What is it also known as?

Dynamic Air Removal Test Bowie Dick test

4 Low temperature sterilization

EO - ETHYLENE OXIDE STERILZATION -low temp gas plasma sterilzatin -low-temp hydrogen peroxide sterilization -hydrogen peroxide-ozone sterilization

Which phase are you actually killing bacteria?

Phase 2 -holding phase/ sterilization/exposure

greatest challenge

Place process challenge devices (PCD =BI test pack) & bowie dick test packs in this location

may be used on sterilizer carts to help with condensate that might drip off the carts onto packs and to help prevent damage to the wrapping material

Shelf Liners

Bowie Dick test :

is used to detect air leaks, inadequate air removal , inadequate steam penetration and the presence of condensable gases. performed Daily for dynamic air removal cycle of prevacuum sterilizers a warm-up cycle is run to properly heat the sterilizer to avoid -for large sterilizers, place flat, facing up on the bottom shelf of the sterilizer cart over the drain in an empty chamber -the test pack should never be placed directly on the floor of the chamber or an instrument tray or wire basket that has turned upside down; it should always be placed in a sterilizer cart

multi-level/ heavy instrument sets

make drying difficult containments systems heavy duty wrapping materials packages should be cooled , opened

What is the absesense of fluorencense?

means that the spores in the BI will not grow further incubation -a new type of early-readout BI uses the same enzyme-based technology and provides a final reading 1 hour after sterilization for 270 dynamic air removal cycles (4 minute exposure time at 270f 3 minute exposure time at 275)

Loading a Sterilizer

metal items should be placed below textile items, allowing condensate to drain out without wetting other items in the load

"damp" or wet packs should ________ be placed inside the sterilizer to "continue" to dry . why?

never Handling wet packs can cause microorganisms to migrate inside the pack, contaminating the contents

18 minutes 273f pre-vac cycle :

recommended cycle for processing decontaminated instruments from a suspected CJD

Test procedures for Routine BI Monitoring : for sterilizers larger than 2 cubic feet

should be placed flat, facing up, in the area of the sterilizer least favorable for sterilization (the area that represents the greatest challenge to the PCD, which is usually the bottom shelf of the sterilizer cart over the drain line) in a fully loaded chamber. -to ensure correct placement, the BI PCD should be placed in the sterilizer cart FIRST, before loading the other items for sterilization -after sterilization process, PCD should be allowed to cool, for the length of time specified by the manufacturer -BI vial is then removed from the PCD and labeled: sterilizer number, cycle number and date -the test BI Vial and the control BI vial from the same lot should be activated and incubated according to the MI manufacturer IFU -BI test and control vials should be read at the appropriate time and results documented

The three parameters of sterilization are:

steam under pressure, time and temperature

When heat is added to steam without increasing the moisture content, the steam is called

superheating

Inspect sterilized packs for what?

tears and holes

in a mixed load (textile items and metal goods) :

textile packs and paper plastic pouches should be placed on the top shelf/rack while metal instruments, basins and other metal items are placed in the lower shelves -prevents condensate of metal instruments from dripping onto the packs below, making them wet.